Mark 46 torpedo


The Mark 46 torpedo is the backbone of the United States Navy's lightweight anti-submarine warfare torpedo inventory and is the NATO standard. These aerial torpedoes are designed to attack high-performance submarines. In 1989, an improvement program for the Mod 5 to the Mod 5A and Mod 5A increased its shallow-water performance. The Mark 46 was initially developed as Research Torpedo Concept I, one of several weapons recommended for implementation by Project Nobska, a 1956 summer study on submarine warfare.

Design details

Variants

  • Mod 0: One of the original versions of 1960. Solid propellent piston engine. Gyro/wire guidance with passive/active homing.
  • Mod 1: Based on Mod 0. 1967. Uses liquid Otto fuel piston engine. Laminar search guidance. Phase 1 of 1968 uses stronger hull to resist deeper waters. Phase 2 of 1971 uses a new homing program able to detect submarines near the surface.
  • Mod 2: Based on Mod 1 phase 2. More powerful Mk 103 Mod 1 warhead. Improved computer with snake search pattern capability. Known to have been captured by China in 1978.
  • Mod 4: Version for use as Mark 60 CAPTOR mine payload.
  • Mod 5: 1979 upgrade kit for Mod 2, also known as NEARTIP. New passive/active sonar, liquid fuel and two speed engine for low speed search and high speed attack.
  • * Mod 5A: Cheaper NEARTIP upgrade kit for Mod 1 and Mod 2 with improved shallow-water performance. 1980s.
  • * Mod 5A: Variant of 5A that allows use in water as shallow as 40 m.
  • * Mod 5A: Latest variant from 1996 Service Life Extension Program. Boasts improved counter-countermeasure performance, enhanced target acquisition, provides a bottom-avoidance preset, and improved maintainability and reliability.
  • Mod 6: Version for Mark 60 CAPTOR, with some NEARTIP components.
  • Mod 7: Cancelled. Not funded by Congress.
For most variants there is also an inert REXTORP version.

Specifications

; Mark 46, Mod 5
  • Primary Function: Air and ship-launched lightweight torpedo
  • Contractor: Alliant Techsystems
  • Power Plant: Two-speed, reciprocating external combustion; Mono-propellant
  • Length: tube launch configuration, with ASROC rocket booster
  • Weight:
  • Diameter:
  • Range:
  • Depth: >
  • Speed: >
  • Guidance System: Homing mode: Active or passive/active acoustic homing
  • Launch/search mode: Snake or circle search
  • Warhead: of PBXN-103 high explosive
  • Date Deployed: 1967 ; 1979

Yu-7 variant

The Chinese Yu-7 torpedo is said to be based on the Mk 46 Mod 2. The People's [Liberation Army Navy|Chinese Navy] used the Yu-7 ASW torpedo, deployed primarily on ships and ASW helicopters, but it started to be replaced by the Yu-11 in 2012.